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Date: Sun, 29 Jan 2006 22:46:42 +0100
From: Erik Trulsson <ertr1013@student.uu.se>
To: Norberto Meijome <freebsd@meijome.net>
Message-ID: <20060129214642.GA10318@student.uu.se>
References: <43DD3341.4070103@meijome.net>
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Cc: FreeBSD Questions <freebsd-questions@freebsd.org>
Subject: Re: gcc options when building kernel
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On Mon, Jan 30, 2006 at 08:27:29AM +1100, Norberto Meijome wrote:
> Hi all,
> I'm rebuilding my kernel and I noticed some gcc (I believe ) options 
> being used that I don't think I set anyway.
> 
> The options are :
> -mno-mmx -mno-3dnow -mno-sse -mno-sse2
> 
> Does this mean that the kernel won't make use of these cpu features, 
> even though they are supported by the cpu (see below)

Correct.  The CPU registers associated with those CPU features must not be
used inside the kernel, and therefore the build process explicitly disables
them to avoid any mistakes.


-- 
<Insert your favourite quote here.>
Erik Trulsson
ertr1013@student.uu.se